﻿<blockquote class="extDef">NOTE&nbsp; Definition according to ISO/CD 10303-42:1992<br>
This function returns the normalized vector that is simultaneously the
projection of arg onto the plane normal to the vector z-axis and onto
the plane normal to the vector x-axis. If arg is NULL then the
projection of the vector (0.,1.,0.) onto z-axis is returned.</blockquote>

<blockquote class="note">NOTE&nbsp; Function adapted from <strong>second_proj_axis</strong> defined in ISO 10303-42.</blockquote>
<blockquote class="history">HISTORY&nbsp; New function in IFC2x</blockquote>
